Endangered Mammals - Wolves

Wolves were once among the most widely distributed mammals on Earth. Prior to European settlement, wolves FIGURE 7.2
Northern Idaho ground squirrel probable historical distribution and primary/secondary metapopulation sites, 2003 ranged over most of North America, from central Mexico to the Arctic Ocean. Their decline has largely resulted from hunting. In 1914 Congress authorized funding for

TABLE 7.2
Listing factors and threats for the northern Idaho ground squirrel

Listing factor	Threat	Still a threat?
A	Forest encroachment into grassland meadows/fire suppression	Yes
A	Conversion of meadows to agriculture	Yes
A	Grazing practices	Unknown/needs evaluation
A	Residential construction	Yes
A	Development of recreational facilities, e.g., golf courses	Yes
A	Dam expansion for irrigation	Yes
A	Road construction and maintenance	Yes
B	Recreational shooting	Yes
C	Predation, primarily by badgers	Yes
C	Disease, plague	Potential only
D	Inadequate local land use ordinances relating to housing developments	Yes
E	Land ownership patterns	Yes
E	Winter mortality	Yes
Listing factors:
A. The present of threatened destruction, modification, or entailment of its habitat or range
B. Overutilization for commercial, recreational, scientific, educational purposes (not a factor)
C. Disease or predation
D. The inadequacy of existing regulatory mechanisms
E. Other natural or man made factors affecting its continued existence
SOURCE: Adapted from "Table 4. Cross-Reference of Recovery Actions and Listing Factors for the Northern Idaho Ground Squirrel," in Recovery Plan for the Northern Idaho Ground Squirrel (Spermophilus brunneus brunneus), U.S. Fish and Wildlife Service, Region 1, Portland, OR, July 2003

the removal of all large predators, including wolves, from federal lands. By the 1940s wolves had been eliminated from most of the contiguous United States. In 1973 the wolf, which had all but disappeared, became the first animal listed as endangered under the Endangered Species Act. Two species of wolves exist in North America today, the red wolf and the gray wolf. Both are imperiled.

The Gray Wolf Reintroduction Program

In 1991 Congress instructed the Fish and Wildlife Service to prepare an environmental impact report on the possibility of reintroducing wolves to habitats in Yellowstone National Park and central Idaho. Reintroductions began in 1995, when fourteen Canadian gray wolves were released in Yellowstone National Park.

Wolf reintroductions were not greeted with universal enthusiasm. Ranchers, in particular, were concerned that wolves would attack livestock. They were also worried that their land would be open to government restrictions as a result of the wolves' presence. Some ranchers said openly that they would shoot wolves they found on their land. Several measures were adopted to address ranchers' concerns. The most significant was that ranchers would be reimbursed for livestock losses from a compensation fund maintained by the Defenders of Wildlife, a private conservation group based in Washington, D.C. As of 2004 the FIGURE 7.3
Wolf breeding pairs in the northern Rocky Mountain states, 1979–2002 fund had paid out $359,124 to 295 ranchers, covering the losses of 399 cattle, 1001 sheep, and 49 other animals killed by wolves.

Nonetheless, wolf introductions were legally challenged in 1997, when the American Farm Bureau Federation initiated a lawsuit calling for the removal of wolves from Yellowstone. The farm coalition scored an initial victory, but in January 2000 the 10th Circuit Court of Appeals in Denver overturned the decision upon appeal by the United States Department of the Interior, the World Wildlife Fund, and other conservation groups.

As of 2002 the FWS had reintroduced forty-one wolves into Yellowstone and thirty-five wolves into central Idaho. Wolf packs in both Yellowstone and Idaho have thrived. Figure 7.3 shows the number of breeding pairs in northwest Montana, Yellowstone, and Central Idaho from 1979 to 2002. A map of the wolf recovery area is shown in Figure 7.4.

Despite the concern of ranchers and livestock owners, a recovered wolf population in the Yellowstone Park area has only slightly reduced populations of cattle, sheep, elk, moose, bison, and deer. In fact, wolves weed out sick and weak animals, thus improving the overall health of prey populations. Wolf predation on herbivorous species also takes pressure off vegetation and produces carrion for an array of scavengers including eagles, ravens, cougars, and foxes. Finally, wolves have increased visitor attendance to Yellowstone National Park, generating an estimated $7–10 million in additional net income each year.

In 2002 the wolf population in the continental United States was estimated at 3,500 individuals. The gray wolf was officially reclassified by the Fish and Wildlife Service from endangered to threatened in March 2003, and delisted in areas outside the western and eastern recovery regions.

The Mexican Gray Wolf

In 1998 the Fish and Wildlife Service began to reintroduce rare Mexican gray wolves, the smallest of North America's gray wolves, into federal lands in the Southwest. This distinct subspecies once occupied habitats in central and southern Arizona, central New Mexico, western Texas, and northern Mexico. The Mexican gray wolf had been hunted to near extinction in the late 1800s and early 1900s in the United States. By 1960 only seven individuals survived in captivity. Captive breeding programs in the U.S. and Mexico have helped to increase population numbers. Released Mexican gray wolves are being tracked using radio collars. Subsequent releases are expected to create a viable population of one hundred individuals by 2005.

The Red Wolf

The red wolf (see Figure 7.5) was once found throughout the eastern United States, but declined as a FIGURE 7.4
Central Idaho, northwest Montana, and Greater Yellowstone wolf recovery areas, 2002 result of habitat loss and aggressive hunting by humans. It has been considered endangered since 1967. The red wolf is a smaller species than its relative, the gray wolf, and, despite its name, may have any of several coat colors including black, brown, gray, and yellow. In 1975, to prevent the immediate extinction of this species, the Fish and Wildlife Service captured the twenty-some remaining individuals and began a captive breeding program. The red wolf reintroduction program began in 1987, marking the first reintroduction of a species extinct in the wild. Red wolves now reside over about one million acres in North Carolina and Tennessee, including three National FIGURE 7.5
The red wolf is one of the most endangered animals in the world, with an estimated population of less than 300. (U.S. Fish and Wildlife Service) Wildlife Refuges, a Department of Defense bombing range, some state-owned lands, and private property (with the permission and cooperation of landowners). As of 2002 there are nearly one hundred red wolves in these populations, with about 90 percent of these born in the wild. There are also approximately two hundred red wolves managed among captive-breeding facilities around the lower forty-eight states.